from sympy.matrices.expressions import Identity
from .visualization_frame import VisualizationFrame
__all__ = ['PerspectiveCamera', 'OrthoGraphicCamera']
[docs]class PerspectiveCamera(VisualizationFrame):
"""
Creates a Perspective Camera for visualization.
The camera is inherited from VisualizationFrame,
It can be attached to dynamics objects, hence we can
get a moving camera. All the transformation matrix generation
methods are applicable to a Perspective Camera.
Like VisualizationFrame,
It can also be initialized using:
1)Rigidbody
2)ReferenceFrame, Point
3)ReferenceFrame, Particle
Either one of these must be supplied during initialization
Unlike VisualizationFrame, It doesnt require a Shape argument.
Parameters
==========
name : str
a name for the PerspectiveCamera(optional). Default is 'unnamed'
fov : int or float
Field Of View, It determines the angle between the top and bottom
of the viewable area(in degrees). Default is 45 (degrees)
near : int or float
The distance of near plane of the PerspectiveCamera.
All objects closer to this distance are not displayed.
far : int or float
The distance of far plane of the PerspectiveCamera
All objects farther than this distance are not displayed.
"""
def __init__(self, *args, **kwargs):
"""
Initialises a PerspectiveCamera object.
To initialize a visualization frame, we need to supply
a name(optional), a reference frame, a point,
field of view(fov) (optional), near plane distance(optional)
and far plane distance(optional).
Examples
========
>>> from pydy_viz import VisualizationFrame, Shape
>>> from sympy.physics.mechanics import \
ReferenceFrame, Point, RigidBody, \
Particle, inertia
>>> from sympy import symbols
>>> I = ReferenceFrame('I')
>>> O = Point('O')
>>> shape = Shape()
>>> #initializing with reference frame, point
>>> camera1 = PerspectiveCamera('frame1', I, O)
>>> Ixx, Iyy, Izz, mass = symbols('Ixx Iyy Izz mass')
>>> i = inertia(I, Ixx, Iyy, Izz)
>>> rbody = RigidBody('rbody', O, I, mass, (inertia, O))
>>> # Initializing with a rigidbody ..
>>> camera2 = PerspectiveCamera('frame2', rbody)
>>> Pa = Particle('Pa', O, mass)
>>> #initializing with Particle, reference_frame ...
>>> camera3 = PerspectiveCamera('frame3', I, Pa)
"""
try:
self._fov = kwargs['fov']
except KeyError:
self._fov = 45
try:
self._near = kwargs['near']
except KeyError:
self._near = 1
try:
self._far = kwargs['far']
except KeyError:
self._far = 1000
#Now we use same approach as in VisualizationFrame
#for setting reference_frame and origin
i = 0
#If first arg is not str, name the visualization frame 'unnamed'
if isinstance(args[i], str):
self._name = args[i]
i += 1
else:
self._name = 'unnamed'
try:
self._reference_frame = args[i].get_frame()
self._origin = args[i].get_masscenter()
except AttributeError:
#It is not a rigidbody, hence this arg should be a
#reference frame
try:
dcm = args[i]._dcm_dict
self._reference_frame = args[i]
i += 1
except AttributeError:
raise TypeError(''' A ReferenceFrame is to be supplied
before a Particle/Point. ''')
#Now next arg can either be a Particle or point
try:
self._origin = args[i].get_point()
except AttributeError:
self._origin = args[i]
#basic thing required, transform matrix
self._transform = Identity(4).as_mutable()
def __str__(self):
return 'PerspectiveCamera: ' + self._name
def __repr__(self):
return 'PerspectiveCamera'
@property
def fov(self):
"""
attribute for Field Of view of a PerspectiveCamera
Default is 45 degrees
"""
return self._fov
@fov.setter
[docs] def fov(self, new_fov):
if not isinstance(new_fov, (int, str)):
raise TypeError(''' fov should be supplied in
int or float ''')
else:
self._fov = new_fov
@property
def near(self):
"""
attribute for Near Plane distance of a PerspectiveCamera
Default is 1
"""
return self._near
@near.setter
[docs] def near(self, new_near):
if not isinstance(new_near, (int, str)):
raise TypeError(''' near should be supplied in
int or float ''')
else:
self._near = new_near
@property
def far(self):
"""
attribute for Far Plane distance of a PerspectiveCamera
Default is 1000
"""
return self._far
@far.setter
[docs] def far(self, new_far):
if not isinstance(new_far, (int, str)):
raise TypeError(''' far should be supplied in
int or float ''')
else:
self._far = new_far
[docs] def generate_visualization_dict(self):
"""
Returns a dictionary of all the info required
for the visualization of this Camera
Before calling this method, all the transformation matrix
generation methods should be called, or it will give an error.
Returns
=======
a dictionary containing following keys:
name : name of the PerspectiveCamera
fov : Field Of View of the PerspectiveCamera
simulation_matrix : a N*4*4 matrix, converted to list, for
passing to Javascript for animation purposes, where N is the
number of timesteps for animations.
"""
self._data = {}
self._data['name'] = self.name
self._data['type'] = self.__repr__()
self._data['fov'] = self.fov
self._data['near'] = self.near
self._data['far'] = self.far
try:
self._data['simulation_matrix'] = self._visualization_matrix.tolist()
except:
#Not sure which error to call here.
raise RuntimeError('''Please call the numerical
transformation methods,
before generating simulation dict ''')
return self._data
[docs]class OrthoGraphicCamera(VisualizationFrame):
"""
Creates a OrthoGraphic Camera for visualization.
The camera is inherited from VisualizationFrame,
It can be attached to dynamics objects, hence we can
get a moving camera. All the transformation matrix generation
methods are applicable to a Perspective Camera.
Like VisualizationFrame,
It can also be initialized using:
1)Rigidbody
2)ReferenceFrame, Point
3)ReferenceFrame, Particle
Either one of these must be supplied during initialization
Unlike VisualizationFrame, It doesnt require a Shape argument.
Parameters
==========
name : str
a name for the PerspectiveCamera(optional). Default is 'unnamed'
near : int or float
The distance of near plane of the PerspectiveCamera.
All objects closer to this distance are not displayed.
far : int or float
The distance of far plane of the PerspectiveCamera
All objects farther than this distance are not displayed.
"""
def __init__(self, *args, **kwargs):
"""
Initialises an OrthoGraphicCamera object.
To initialize a visualization frame, we need to supply
a name(optional), a reference frame, a point,
near plane distance(optional)
and far plane distance(optional).
Examples
========
>>> from pydy_viz import OrthoGraphicCamera
>>> from sympy.physics.mechanics import \
ReferenceFrame, Point, RigidBody, \
Particle, inertia
>>> from sympy import symbols
>>> I = ReferenceFrame('I')
>>> O = Point('O')
>>> shape = Shape()
>>> #initializing with reference frame, point
>>> camera1 = OrthoGraphicCamera('frame1', I, O)
>>> Ixx, Iyy, Izz, mass = symbols('Ixx Iyy Izz mass')
>>> i = inertia(I, Ixx, Iyy, Izz)
>>> rbody = RigidBody('rbody', O, I, mass, (inertia, O))
>>> # Initializing with a rigidbody ..
>>> camera2 = OrthoGraphicCamera('frame2', rbody)
>>> Pa = Particle('Pa', O, mass)
>>> #initializing with Particle, reference_frame ...
>>> camera3 = OrthoGraphicCamera('frame3', I, Pa)
"""
try:
self._near = kwargs['near']
except KeyError:
self._near = 1
try:
self._far = kwargs['far']
except KeyError:
self._far = 1000
#Now we use same approach as in VisualizationFrame
#for setting reference_frame and origin
i = 0
#If first arg is not str, name the visualization frame 'unnamed'
if isinstance(args[i], str):
self._name = args[i]
i += 1
else:
self._name = 'unnamed'
try:
self._reference_frame = args[i].get_frame()
self._origin = args[i].get_masscenter()
except AttributeError:
#It is not a rigidbody, hence this arg should be a
#reference frame
self._reference_frame = args[i]
i += 1
#Now next arg can either be a Particle or point
try:
self._origin = args[i].get_point()
except AttributeError:
self._origin = args[i]
#basic thing required, transform matrix
self._transform = Identity(4).as_mutable()
def __str__(self):
return 'OrthoGraphicCamera: ' + self._name
def __repr__(self):
return 'OrthoGraphicCamera'
@property
def near(self):
"""
attribute for Near Plane distance of an OrthoGraphicCamera
Default is 1
"""
return self._near
@near.setter
[docs] def near(self, new_near):
if not isinstance(new_near, (int, str)):
raise TypeError(''' near should be supplied in
int or float ''')
else:
self._near = new_near
@property
def far(self):
"""
attribute for Far Plane distance of an OrthoGraphicCamera
Default is 1000
"""
return self._far
@far.setter
[docs] def far(self, new_far):
if not isinstance(new_far, (int, str)):
raise TypeError(''' far should be supplied in
int or float ''')
else:
self._far = new_far
[docs] def generate_visualization_dict(self):
"""
Returns a dictionary of all the info required
for the visualization of this Camera
Before calling this method, all the transformation matrix
generation methods should be called, or it will give an error.
Returns
=======
a dictionary containing following keys:
name : name of the OrthoGraphicCamera
simulation_matrix : a N*4*4 matrix, converted to list, for
passing to Javascript for animation purposes, where N is the
number of timesteps for animations.
"""
self._data = {}
self._data['name'] = self.name
self._data['type'] = self.__repr__()
self._data['near'] = self.near
self._data['far'] = self.far
try:
self._data['simulation_matrix'] = self.simulation_matrix.tolist()
except:
#Not sure which error to call here.
raise RuntimeError('''Please call the numerical
transformation methods,
before generating simulation dict ''')
return self._data